Invalid partition scheme in sort if intermediate projection has dropped a partition column

**Describe the bug**
I am hitting this error with benchmark query 3 in ray-sql:

```
physical_plan::to_proto() unsupported expression UnKnownColumn { name: "ps_supplycost" }
```

Here is some debug output that I think shows the root cause. This is from walking down the plan. There is a join that uses `ps_supplycost` as a join key so the partitioning scheme includes `ps_supplycost`. This column is then dropped in a projection, but the `SortExec`'s partition scheme still uses `ps_supplycost`.

```
plan = SortExec: [s_acctbal@0 DESC,n_name@2 ASC NULLS LAST,s_name@1 ASC NULLS LAST,p_partkey@3 ASC NULLS LAST]

partitioning_scheme = Hash([Column { name: "p_partkey", index: 3 }, UnKnownColumn { name: "ps_supplycost" }], 4)
---

plan = ProjectionExec: expr=[s_acctbal@5 as s_acctbal, s_name@2 as s_name, n_name@7 as n_name, p_partkey@0 as p_partkey, p_mfgr@1 as p_mfgr, s_address@3 as s_address, s_phone@4 as s_phone, s_comment@6 as s_comment]

partitioning_scheme = Hash([Column { name: "p_partkey", index: 3 }, UnKnownColumn { name: "ps_supplycost" }], 4)
---

plan = ProjectionExec: expr=[p_partkey@0 as p_partkey, p_mfgr@1 as p_mfgr, s_name@8 as s_name, s_address@9 as s_address, s_phone@11 as s_phone, s_acctbal@12 as s_acctbal, s_comment@13 as s_comment, n_name@15 as n_name]

partitioning_scheme = Hash([Column { name: "p_partkey", index: 0 }, UnKnownColumn { name: "ps_supplycost" }], 4)
---

plan = CoalesceBatchesExec: target_batch_size=8192

partitioning_scheme = Hash([Column { name: "p_partkey", index: 0 }, Column { name: "ps_supplycost", index: 6 }], 4)
---

plan = HashJoinExec: mode=Partitioned, join_type=Inner, on=[(Column { name: "p_partkey", index: 0 }, Column { name: "ps_partkey", index: 0 }), (Column { name: "ps_supplycost", index: 6 }, Column { name: "__value", index: 1 })]

partitioning_scheme = Hash([Column { name: "p_partkey", index: 0 }, Column { name: "ps_supplycost", index: 6 }], 4)
---
```

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**Expected behavior**
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Start by reproducing benchmark query 3 in ray-sql and inspect the plan from HashJoinExec through CoalesceBatchesExec, ProjectionExec, and SortExec. Trace the partitioning scheme into physical_plan::to_proto(); done means a dropped ps_supplycost column is not retained in the SortExec partition scheme and serialization no longer reports an UnKnownColumn.

Written by the indexing model from the issue text.